1. Field of the Invention
This invention pertains generally to assessing distribution within a related data set, and more particularly to a method of quantifying the distribution of pixel characteristics within images.
2. Description of Related Art
Increasing attention is being directed to methods of multimedia categorization. Perhaps one reason for this stems from the inclusion of content on the web and on organizational databases, and the requisite need of searching through a vast content store to select the desired content. Categorization as to proportion of colors is well known, however, this factor alone can be very misleading. Colors within an image are subject to different distributions according to the subject. For example, an image of a person wearing a red shirt may not be distinguished from a scattered field of red flowers.
One researcher has attempted to use histogram refinement to provide content-based image retrieval, in which an attempt is made to classify images with similar color histograms but with different spatial coherence. The method uses color coherence vectors in which pixel groups are determined by computing connected components, wherein only pixels in the same class are compared. However, this method is only effective when pixels form connected groups, while it does not distinguish groups with different shapes and variations. Furthermore, this method is unable to evaluate the pixel distribution at different resolution scales.
Accordingly a need exists for a method of evaluating the distribution of pixel characteristics within images. The present invention fulfills that need and others and can be readily implemented with low processing overhead on both new and existing systems.